Antenna rotator



E. L. BARRETT ANTENNA ROTATOR Feb. 9, 1954 2 Sheets-$heet 1 Filed Aug. 22, 1951 INVENTOR. Edward L. Barre:

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Patented Feb. 9, 1954 UNITED STATEfi ATENT OFFICE ANTENNA ROTATOR Edward L. Barrett, La, Grange, Ill.

Application August 22, 1951, Serial No. 243,108

9 Claims. 1.

This. invention relates to remotely controllable rotators for adjusting: the rotary position of directional antennas. Such rotators are widely used in connection with the reception of television and other high frequency radio signals, in order that signals from any desired direction may be received with maximum efficiency.

An object of the invention is to provide an antenna rotator which may be coaxially disposed on its stationary supporting mast, or the like, and which carries the antenna. in a coaxial relationship withthe mast. As a result of this arrang ment, the rotator imposes only an end thrust on the mast, without imposing any bending stress. Moreover, the rotator presents an unusually pleasing functional appearance.

A further object is to provide a rotator in which the working parts are enclosed a cir cular housings, which rotates with the antenna, the housing being rotatacly supported on a sta-- tionary central mern which extends upwardly into the housing. t is a related object to provide unusually effective sealing means to exclude dust and water from the working parts, the sealing means being interposed between the housing and the stationary supporting member.

A further object is to provide an antenna 110-- tator which is unusually sturdy and dependable, but nevertheless inexpensive and relatively easy to manufacture.

Further objects, advantages, and features of the invention will appear from the following description of an illustrative embodiment, the description being taken with the drawings, in which:

Figure 1 a perspective view of an antenna installation including an antenna rotator embodying the features of the invention;

Fig. 2 is perspective view on a larger scale of the antenna rotator; I

Fig. 3 is a perspective View or" the rotator,

partly in axial section to illustrate details of the driving mechanism for producing: antenna rotation;

Fig. is a horizontal sectional view of the up- 1 r per portion of the rotator, taken along, a line rotatable antenna mast section [2.

While the invention is susceptible of various modifications and alternative constructions, there is shown in the drawings and will herein be described in detail the preferred embodiment, but it is to be understood, however, that there is no intention to limit the invention to the form disclosed, but, it is intended to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

Referring now to Fig. 1 of the drawings, the antenna installation includes a conventional television antenna ill suitably mounted upon a A fixed mast section i l is disposed in coaxial alinement with the rotatable mast section It, and the two sections are coupled together for rotation of the section 1 2 with respect to the section Hi by means an antenna rotator 15 including a housing" it which is disposed all or the control elements and instrumentalities provided to eiiect rotation of the antenna under the control of a remotely located control station. The means for remotely controlling the orientation of the antenna is fully described and specifically claimed in my copending application entitled Directional Control Mechanism for Antennas, Serial No. 230,266, filed. June 7, 1951, to which reference may be had to supplement the brief description contained in this application.

The housing It has a closed upper wall ll provided with a coaxially disposed, upwardly projecting post is (Fig. 3) which is adapted to be inserted into the lower end of the rotatable mast section 12. In order to accommodate masts of various internal diameters, the post ill is provided with a split upwardly tapering conical bushing- 2d therearound having an axial bore therein for reception of the post. It will be apparent that masts of relatively small internal diameters will engage the bushing 2e adjacent the upper region thereof, while masts of larger internal diameters will move further downwardly on the bushing.

The rotatable mast section 12 is mounted in coaxial relationship on the housing I5 by means of a supporting structure which is fully described and specificall claimed in my copending application Serial No. 230,268, filed June '7, 1951, and entitled Antenna Mast Clamp, to which reference may be had to supplement the following brief description. The supporting structure includes an expansiole and contractible clamping band 2:! (Fig. 2) adapted to engage the mast section 12 at a region spaced upwardly above the housing I6 and a similar contractible band 22 adapted to engage the housing It. A series of struts or supports 24 serves to connect the two bands 2I and 22 and maintain the rotatable mast structure or section 12 upright.

The housing It is formed in two sections including an upper bell-shaped section 23 and a lower generally tubular section 28, the two sections being suitably secured together as by means of attachment screws 38.

The upper end of the non-rotatable mast section I4 is adapted to be received within a clamping mechanism 32, which is fully described and specifically claimed in the previousl mentioned copending application, entitled Antenna Mast Clamp, Serial No. 230,268, filed June 7, 1951. Briefly, the clamping mechanism 32 includes an inverted socket member 33 to which there is secured a plurality of axially extending clamping arms 34. Sectional clamping bands 36 which are 1.:

in turn secured to the arms 3 include screws for applying peripheral gripping pressure to the upper end of the mast section.

The clamping mechanism 32 supports a stationary cage or framework 35 (Fig. 3) upon which 1.

there is supported an electrical driving motor M for rotating the antenna III. In accordance with a feature of the invention, rotation of the antenna is obtained by rotating the housing I6 to which the antenna mast section I2 is fixedly secured. The framework 35 i supported in turn by a U-shaped lower bracket 36 having arms 35a and 381) which straddle the framework and which are fastened thereto by screws or the like (see Fig. 4). The bracket 36 is fixedly mounted on the mast-receiving socket member 33 by means of a post or pillar 37 (Fig. 7), which has upper and lower threaded shanks 3B and 33 extending through apertures 40 and M in the bracket and the socket member respectively. The bracket and the socket member are clamped between upper and lower shoulders 42 and 43 on the pillar and upper and lower nuts 44 and 45 threaded on the shanks 38 and 39.

The cage or framework 35 (Fig. 3) is provided with a top wall 48 to which there is secured an inverted U-shaped bracket 4'! (Figs. 3 and l). The motor M is provided with a motor shaft 48 on which there is mounted a gear pinion 49 (Figs. 3 and 4) which meshes with a larger gea 51'! mounted on a shaft 52 journaled between the top wall 46 of the cage and the bracket 47. A pinion 54, which may be integrally formed with the gear 50, meshes with a larger gear 56 carried on a shaft 53 1ikewise journaled between the top wall 46 of the cage 35 and the bracket 47. A pinion 68, which may be integrally formed with a gear 53, meshes with a gear 62 mounted on a shaft 64 rotatably journaled between the top wall 46 of the cage 35 and the upper portion of a second inverted U-shaped bracket 66 suitably secured to the cage 4|. A gear 68 is secured to the shaft 64 and is in constant mesh with a ring gear l0 which is centrally disposed within the upper casing section 26 and is secured in position by means of a series of radially spaced anchoring bolts '52. The ring gear I9 is recessed centrally to provide a socket II therein for reception of a ball thrust bearing 13 rotatively mounted on a post I5 carried on the bracket 47. The bearing I3 absorbs substantially all of the downward vertical thrust of the antenna installation. From the above description of parts, it will be seen upon energization of the motor M and consequent rotation of the motor shaft 48 a direct drive will 4 exist through the train of gears including the gears 49, 50, 54, 58, 62, 68 and IE! to th housing IE on which the rotatable mast section I2 is mounted.

The lower section 23 of the housing I6 is provided with a generally cylindrical well portion having an inwardly directed flange 82 (Fig. '7) at its lower end. A resilient sealing ring or gasket 34 is interposed between the housing and the stationary axial clamping or supporting means 32, in order to form a rotary seal to exclude dirt and moisture from the rotatable housing I6. In this instance the gasket fits snugly between the outer surfac of the socket member 33 and the inner surface of the housing well 89. The gasket has a groove 83 to receive th inner edge of the flange 82. A stationary sealing plate 83 abuts against the upper surface of the gasket, the plate t8 being clamped between the socket member 33 and the shoulder 33 on the pillar 31. Thus the gasket is confined between the plate 88 and the flange 82. The clamping arms 34, socket member 33, sealing plate 88 and the sealing gasket 34 are non-rotatable, but the well portion 80 rotates with the housing It and the antenna I8.

A transmission line or lead-in cable 90 is connected at its upper end to the antenna I0. The transmission line is connected to a lower line section 92 by rotatable connecting means 94 (Fig. 7) positioned in the rotator housing I5. The rotatable connecting means enables the antenna to be continuously rotated in one direction. The rotatable connecting means is fully described and specifically claimed in my copending application, Serial No. 230,267, filed June 7, 1951, and entitled Lead-in System for Rotatable Anten nas. Reference may be made to this copending application to supplement the following brief description. The rotatable connecting means 94 includes two stationary insulated slip rings 95 and 98 fixedly supported along the pillar 31. The slip rings are electrically connected to the lower transmission line section 92. The lower end of the upper transmission line section 90 is con nected to a pair of rotatable brushes I90 and I02 which engage the respective slip rings. The lower line section 92 extends from the slip rings through a slot or passage I04 in the sealing gasket 84. The upper line section 98 passes into the housing I5 through an insulating terminal block or bushing I06 which supports the brushes I00 and I92, the terminal block being securely positioned in an opening I83 in the well portion 80 of the housing I6.

A control cable III! (Fig. 7) is connected at its upper end to the motor M and the other instrumentalities for controlling the orientation of the antenna. This control cable not only supplies current to the motor but also carries impulses from a pulsing switch Cl, as more completely described in my previously mentioned application Serial No. 230,266. The cable passes downwardly between the pillar 3'! and the slip rings 96 and 93, and thence out of the housing 33 through an aperture H2 in the gasket-supporting plate 83 and a passage or slot H4 in the gasket 84. The lower end of the control cable is connected to a terminal block I I3 which is mounted on one of the clamping arms 39. A control cable extension I It extends from the terminal block IIB to the control station (not shown).

Although the operation of the rotator will be apparent from the preceding description, the operation will be briefly summarized. The antenna Hi is rotated by energizing the motor M. The energization of the motor may be. controlled from a remote control station (not shown.) by means of the control cable H0; H8- in a manner which is fully described in the previously men.- tioned copending application Serial No. 230,266. By means oi the intermediate gears 513', 54, 55-, Bil, 62, and E8, the rotation of the motor pinion to produces rotation of the ring. gear it secured to the top wall ll of the housing it. lhe housing thereby is rotated onthe thrust bearing. 73. The rotation of the housing produces rotation of the upper antenna mast section 12' in coaxial relationship with the lower mast clamp $2, the latter providing a stationary support for the motor and the driving gears.

The ring-shaped gasket 34 and the gasltetsupporting plate 88 remain stationary along with the socket member 33, but the lower well portion 80- rotates along \vitl'l the housing 16 so thrrt the inner surface of. the well portion slides over the outer surface of the gasket M. The inwardly directed flange 82 at the downwardly directed mouth of the housing rotates in its retaining groove 86 in the gasket.

As stated, the downwardly directed thrust of the antenna ii) and the upper mast section. I2 is carried by the thrust bearing 73 so that the gasket 84 is relieved of any substantial thrust. However, the gasket and the gasli'et suppora ing plate $8 provide acertain amount of lateral support tending to maintain the coaxial aline ment of the upper and lower mast sections l2 and I4.

It is to be noted that the gasket is protected by reason of its position and arrangement against the entrance of dirt and moisture and the collection of ice and sleet.

Any ice which does form on the gasket to does not unpair the operation of the rotator because the resilient gasket is flexed slightly under the driving torque provided by the motor and the ice is thereby cracked off the gasket.

As the housing It rotates, the rotatable brushes I00 and I92 slide along the stationary slip rings 96 and 98. Thus, the slip rings and the brushes provide a rotatable signal-carrying connection between the upper and lower transmission line sections 80 and 92. By virtue of the rotatable connection, it is possible to rotate the antenna continuously in one direction.

Assembly and servicing of the rotator are greatly simplified by the provision of the separrable upper and lower housing sections 2.6 and 28. the housing to be narrow so that an efiective rotatable seal may be easily and inexpensively provided.

In the event service becomes necessary, the upper portion 25 of the housing may be freed by unscrewing the screws 30 and then sliding such portion axially (upward). To facilitate this, one of the bearing rolls, or both, may have a sliding fit. The gear it on the housing will be disengaged from the driving train and the entire mechanism is exposed for inspection and service. If desired, the entire framework which mounts the motor and gear train may be easily detached from the bracket it and replaced with a similar drive unit.

Since the entire housing it rotates about the stationary axial mast clamp or supporting member 32, the housing is inherently maintained in coaxial relationship with the supporting member. Because the entire housing is rotated. the

This construction permits the mouth of iii rotatable sealing means is: unusually effective for excluding dust and moisture.

A simple and. inexpensive mechanical construction results from mounting the motor M and the drive gears on the stationary support 35 inside the housing.

The present application is a continuation-inpart of my copending applications Serial Nos. 230,266, 230,267 and 230,268, filed on June 7, 1951.

I claim as my invention:

I. In an antenna rotator, the combination comprising a stationary base; means at the underside of said base for supporting the same; a driving mechanism on said base having a frame, driving motor, and gear train terminating in a drive pinion; an inverted bell-shaped housing telescoped over said drive mechanism; a thrust bearing on said frame in coaxial relationship with said housing for engaging the interior wall thereof for supporting the housing and permitting rotation thereof; means mounted on top of said housing in coaxial relationship therewith for supporting an antenna; and a housing gear coaxially fixed in said housing, said drive pinion being positioned for meshing with said housing gear upon said housing being telescoped over said. driving mechanism and into seated position on said thrust bearing.

2.. In an antenna rotator, the combination comprising a stationary base; supporting means at the underside of said base for coaxial attachment to a supporting pole; a driving mechanism on said base having a frame, driving motor, and gear train terminating in a driving element; an inverted bell-shaped housing telescoped over said driving mechanism; a thrust bearing on said frame in coaxial relationship with said housing and with said supporting means for engaging the interior wall ofi said. housing for supporting the housing and permitting rotation thereof about an axis which is coaxial with respect to the supporting pole; and a driven element fixed to said housing for engaging said driving element in axially disengageable relation thereto for rotation of the housing by said motor; means on the top of said housing in coaxial relationship therewith for supporting an antenna; and a bottom cover peripherally joined to the lower edge of the housing and having a rotatable sealing engagement with said base for sealing the housing against the entry of moisture, said housing having a wide mouth and having a disengageable connection with said bottom cover so that the housing may be axially removed to expose the driving mechanism for service.

3. In an antenna rotator, the combination comprising a stationary base; supporting means at the underside of said base for coaxial attachment to a. supporting pole; a driving mechanism on said base having a frame, driving motor, and gear train terminating in a driving element; an inverted hell-shapedhousing telescoped over said driving mechanism; a thrust bearing on said frame in coaxial relationship with said housing and with said supporting means for engaging the interior wall of said housing for supporting the housing and permitting rotation thereof about an axis which is coaxial with respect to the sup porting pole, and a driven element fixed to said housing for engaging said driving element in axially disengageable relation thereto for rotation of the housing by said motor; means on the top of said housing for supporting an antenna coaxially with respect thereto; said housing hav ing a bottom cover in the shape of an annular flange with outer and inner edges, the outer edge of said flange having a disengageable sealing connection with said housing; and an annular sealing member of rubber or the like between the bottom cover and said base, said sealing member having a diameter which is considerably less than said housing for the production of high breakaway force at the sealing surfaces.

4. In an antenna rotator for rotating an upper antenna-carrying mast relative to a stationary mast, the combination comprising a stationary base, a clamp on the underside of said base for coaxial attachment to the lower mast, a driving mechanism on said base and including a frame and a driving motor, a thrust bearing mounted on said frame in coaxial relationship with said clamp, a bellshaped housing telescoped over said driving mechanism and seated coaxially on said bearing for rotation thereon in coaxial relationship with the lower mast, means connecting said driving motor to said housing for rotating the latter, and a clamp mounted on top of said housing in coaxial relationship therewith for supporting the upper mast coaxially relative to the lower mast.

5. In an antenna rotator for rotating an antenna relative to a stationary mast, the combination comprising a stationary base, supporting means on the underside of said base for coaxial attachment to the mast, a driving mechanism on said base and including a frame and a driving motor, a thrust bearing mounted on said frame in coaxial relationship with said supporting means, a bell-shaped housing telescoped over said driving mechanism and seated coaxially on said bearing for rotation thereon in coaxial relationship with the mast, means connecting said driving motor to said housing for rotating the latter, and means mounted on top of said housing in coaxial relationship therewith for supporting the antenna.

6. In an antenna rotator for rotating an antenna-carrying mast, the combination comprising a stationary base, means at the underside of said base for supporting the same, a driving mechanism on said base and including a frame and a driving motor, a thrust bearing mounted on said frame, a bell-shaped housing telescoped over said driving mechanism and rotatably carried on said bearing in coaxial relationship therewith, means connecting said motor to said housing for rotating the latter, and a clamp mounted on top of said housing in coaxial relationship therewith for supporting the antenna-carrying mast.

7. In an antenna rotator, the combination comprising a stationary base, means at' the underside of said base for supporting the same, a driving mechanism on said base and including a frame and a driving motor, a thrust bearing mounted on said frame. a bell-shaped housing telescoped over said driving mechanism and rotatably carried on said bearing in coaxial relationship therewith, means connecting said motor to said housing for rotating the latter, and means mounted on top of said housing in coaxial relationship therewith for supporting the antenna.

8. In an antenna rotator for rotating an upper antenna-carrying mast relative to a stationary mast, the combination comprising a stationary cylindrical base, a clamp on the underside of v said base for attaching the base coaxially to the lower mast, a driving mechanism on said base including a frame and a driving motor, a thrust bearing mounted on said frame in coaxial relationship with said base, a bell-shaped housing telescoped over said driving mechanism and seated coaxially on said bearing for rotation thereon in coaxial relationship with the lower mast, means connecting said driving motor to said housing for rotating the latter, a clamp mounted on top of said housing in coaxial relationship therewith for supporting the upper mast coaxially relative to said lower mast, said housing having an annular bottom cover with outer and inner edges, the outer edge of said cover having a disengageable sealing connection with said housing, the inner edge of said cover being disposed coaxially around said cylindrical base, a retainingflange mounted on said base and spaced above the inner edge of said cover, and an annular sealing member of rubber or the like having a portion disposed between the inner edge of said cover and said base for supporting said housing against lateral displacement relative to said base, said annular member having an outwardly extending flanged portion at its upper end disposed between said cover and said retaining flange for retaining the housing on said thrust bearing against upward movement relative thereto.

9. In an antenna rotator for rotating an antenna relative to a stationary mast, the combination comprising a stationary cylindrical base, means on the underside of said base for attaching said base coaxially to the mast, a driving mechanism on said base including a frame and a driving motor, a thrust bearing mounted on top of said frame in coaxial relationship with said base, a gear coaxially seated on said thrust bearing, a bell-shaped housing telescoped over said driving mechanism and fixed coaxially to the top of said gear, said driving mechanism having a gear train connected between said driving motor and said gear for rotating said housing coaxially relative to the mast, means mounted on top of said housing in coaxial relationship therewith for supporting the antenna, an annular bottom cover having outer and inner edges, the outer edge of said cover having a disengageable sealing connection with said housing, the inner edge of said cover being disposed coaxially around said cylindrical base, a retaining flange on said base and spaced above the inner edge of said cover, and an annular sealing member of rubber or the like having a portion disposed between the inner edge of said cover and said base for supporting said housing against lateral displacement relative to said base, said annular member having an outwardly extending flanged portion at its upper end disposed between said cover and said retaining flange for retaining the housing against upward movement and thereby maintaining the gear in seated relationship with said thrust bearing.

EDVJARD L. BARRETT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 638,643 Newman et al. Dec. 5, 1899 641,603 Newman et al Jan. 16, 1900 680,804 Newman et al Aug. 20, 1901 1,436,685 Sauerhering Nov. 28, 1922 2,474,210 Abbott June 28, 1949 

